The Boy
by Scarred
Summary: Sherlock meets a boy named Billy. A prequel to The Skull. (Alternate Universe, Potterlock, Established Relationship)


**Disclaimer: I own nothing, except the plot.**

* * *

_Sherlock,_

_I sat down and wrote this as soon as I got back home. Well, granted, it wasn't right when I got back home. I spent time with Mom and Dad and Harry, of course, first. It's weird not being able to use magic here, but I guess I should get used to it. I can hear your voice in my ear, lecturing me. "John, please, we've been in school for six years. Surely you know the rules by now." Yeah, yeah, you git. Hush._

_What are you planning to do on your holiday? I hoped we would be able to come back to school early, to spend our own little Christmas together, but the chances aren't very high now. By the looks of it, Mom and Dad want to run me into the ground. Harry's already managed to escape it (no idea how, but I wish I did). I think she's popped down the road to see her friend from school. I didn't know another family like us lived here. Well, you learn something new every day._

_I know you're probably not too particularly interested in Muggle customs, so I won't bore you with the details of my day tomorrow. And the day after that. And the day after that. And the day after that until I can leave again (can't be sooner). _

_On the car ride home, I saw this neat little shop. From what I could see in the window, it had these trinkets and whatnot. I thought of you. (In other words, be sure to buy me a Christmas present, you idiot.) I might walk down there later. Maybe tomorrow._

_I'm planning to send this through the Muggle post, since I have no other means of transport available. Not sure how long it'll take to get there, but I hope you'll appreciate the gesture all the same. So, if it somehow gets to you tomorrow: I miss you already. How are you? If it comes to you well into your holiday: how was it? I bet it was better than mine. Ignore your family's comments. They don't mean it._

_John_

* * *

Sherlock Holmes lies back in bed, his ankles crossed. He narrows his eyes at the wand in his hands as he runs his fingers against the wood. Sebastian the cat is sleeping against him, head resting on his hip. The feline softly snores—the only sounds in the dark manor. Sherlock glances at his bedroom door before wrapping his fingers around the slender object. He flicks his wrist at the open bedroom window. "_Accio Horcrux book_," he mutters.

Holding his breath, Sherlock waits. He watches the night sky, expecting to see the volume zooming through the air. When several minutes pass, he grows impatient and rolls his eyes. "Long shot," he breathes out, clicking his tongue. He leans his head against the pillow and shuts his eyes, hearing his brother toss over in bed in the next room. He glares at the door and slips his legs over the edge, pushing the covers aside. Sebastian makes a throaty sound as he wakes, stretching and standing on the tips of his paws. Sherlock reaches out a hand and scoops up the animal, cradling him to his chest. He scoots out of bed, tightening his grip on the cat and wand both as he makes his way to the door and out into the hallway.

He looks around the hallway, pleased to see nothing. He turns and goes over to Mycroft's bedroom door. Sebastian's beginning to stir and growl as Sherlock crouches down and places him on the floor. The Siamese cat starts to dart past the teenager, but he is quickly caught by the scruff. Sherlock drags him back and places him in front of the door. He scratches at his shoulder blades and travels down to his back. Sebastian looks up at his owner and lets out a single yowl before settling on the floor, lying on his side. Sherlock reaches over and grabs the wand, placing it in between Sebastian's paws. He slowly stretches up and examines the scene. He smiles and looks at the door once more before ducking into his room.

* * *

His family rises several hours later. First, his mother makes her way around the house, her footsteps light as she presses the balls of her feet down against the wood. Second, only minutes later, his father rummages in the kitchen, the pitter-patter of the family house elf following behind. And third, Mycroft exits the bedroom, a yowl coming from Sebastian before he sprints down the hall. He sighs and the floor creaks. "Oh, Sherlock," he mutters and trails after the cat.

A few minutes pass until the younger Holmes is in the kitchen. He stops in the doorway and studies Mycroft and his father, who are seated at the dining table, completely absorbed in their individual actions—his father, reading the newspaper, Mycroft, eating.

"Here you are, sir!"

Sherlock looks down and spies the elf holding out a plate of breakfast for him. He gives him a smile and slips off the toast. He bites into it and starts across the room. "Thank you, Bunsen."

"How many times do I have to remind you not to leave Sebastian outside of my room? With my wand, of all things." Mycroft narrows his eyes and wrinkles his nose as Sherlock drops into a neighboring chair.

"I lost count," he says, crumbs of toast falling out of his mouth.

Siger Holmes lifts his head and gives his sons a look. "Don't talk with your mouth full, Sherlock."

Sherlock narrows his own eyes and gnashes his teeth on his breakfast. Mycroft gives a smug look as he continues his meal.

"I'm assuming you'll be fine staying home by yourself, then, Sherlock?" Siger says, straightening up, folding his newspaper, and setting it on the table.

"Of course I am." He glances at the front page of the paper, the large picture on the front moving.

"Excellent."

Mycroft snaps, and Bunsen walks over to take his plate. As the elf turns away, Mycroft looks over at Sherlock. "Don't do anything drastic to the place while the adults are off in the real world."

"Now, now, Mycroft, don't patronize Sherlock." Violet Holmes steps into the kitchen, her shoes clicking against the tile. She has her bright-green robes already on, the symbol of Saint Mungo's prominent. "You were in his place before."

The older Holmes brother purses his lips, while the younger gives his own smug look.

* * *

Sherlock stalks through the sitting room, shrugging on his coat. He gives Sebastian a look from where he's stationed on the coffee table. "Don't look at me like that," he growls. Sherlock pats his pockets, making sure he has his wand and some money. "I'm not doing anything wrong." He glances down the hall. "I'll be out, Bunsen! No worries!" Upon hearing the squeak of the house elf, Sherlock slips out of the house.

He gets hit with a blast of cold air and grimaces. He tightens the coat around him and starts down the street. A few kids are running up and down the street, tossing snowballs at each other. No parents are in sight. No doubt comfortably watching from inside. Sherlock shakes his head and bares his teeth as he side-steps past the children.

"Hi."

Sherlock furrows his brow and stops. He turns and looks over, seeing a twelve-year-old boy staring at him. His face is dirty, and his clothes are torn, but his eyes are bright. "Hello?" he says cautiously.

The boy smiles. "My name's Billy."

The teenager looks around, as if to see if this whole situation is really happening. He slowly nods. "I'm Sherlock."

"That's a funny name."

"Billy's a simple name, but you don't see me laughing at you." Billy's eyes widen, and he takes a step back. Sherlock sighs and shakes his head. "Forget it. I have to go. Goodbye, Billy." He turns and continues down the street, leaving the dirty boy behind.

* * *

The small bell above the door dings as Sherlock pushes open the door. He glances at the object before wiping his feet on the mat and shutting the door behind him. He looks around the bookshop, the musty smell of old runebooks and used textbooks reminding him of the library back at Hogwarts. He catches the eye of several other customers, who scurry along before Sherlock even has the opportunity to scrutinize them. He purses his lips and starts towards a shelf, scanning the volumes.

"Do you need any help?" Sherlock turns his head, looking down at a small witch with auburn hair. "I see you're looking at the crafting books." She presses a hand to Sherlock's chest and pushes him back, earning herself a glare. "Aha, the knitting. Well, it is Christmas time." She smiles and looks back at him, hands on her hips. "Making for someone special?"

Sherlock glances at the books. "No, I don't." He furrows his brow and turns to her. "I'm not looking at those. I walked past them."

"You lingered."

"Excuse me?"

"You lingered! Sure, those books might not be your intent, but your subconscious made you slow down."

He narrows his eyes and looks down the aisle, parting his lips. He takes a step back. "I'm looking for the Dark Arts section. I'm presuming you have one?"

The witch frowns and crosses her arms over her chest. "Yeah, but I'm obligated to warn anybody who wants to view those books."

"Why warn? There's nothing to fear anymore—"

"—nobody knows that for sure—"

"—people should be able to read as much as they want—"

"—it's not like they're hidden—"

"—it's not like Voldemort is going to leap out from the shelves and murder everyone—"

"—don't say his name!"

Sherlock smirks. "Don't tell me you're one of those people that still fear him?"

Her cheeks grow a rapid shade of pink. She shakes her head and wrings her hands. "No, no, it's not. No, it's just. You never know what could happen."

He shoves his hands into his pockets and swivels. "May I see the books now?"

She pushes her hair back and turns away, leading the taller to the back section of the store. Sherlock's eyes widen, and he bids her thanks before stepping to the small collection of tomes. He stands near a section and scans the spines, going through the Bs. With no results, he furrows his brow when he hits the Cs. He reaches out and touches the space between the letter jump. He stays still and takes a deep breath. "Of course," he mutters. "They don't have it." Straightening up, he steps out of the section and pokes his head out. He spies the witch by the front counter, reading through a magazine. Sherlock walks towards her. "You don't happen to have _Secrets of the Darkest Art_ by Owle Bullock, do you?"

The witch lifts up her head and bites her lip. "Isn't it back there?" she asks, even though her tone suggests that she already knows the answer.

"No," Sherlock spits out. He narrows his eyes, starting to shake his head. "Next, you're going to tell me those were taken out everywhere."

She looks down at her magazine and nervously plays with a strand of her hair. "You know the stories."

Huffing, he looks off to the side. "Then I have no use here." The other glances at him for a split second, making Sherlock sigh again. "Just give me one of those other books. The knitting ones." She smiles, shutting her magazine and waving her wand towards the shelf.

* * *

Sherlock unhappily leaves the bookshop, his purchase tucked underneath his arm. He stalks down the street, keeping his head down low as he passes other witches and wizards. He needs that book, but if it was removed from the Hogwarts library in the 1950s and virtually disappeared anywhere else, he doesn't really have the highest chances of obtaining it. He scoffs and rolls his eyes. "If that Granger girl can get it, why can't I?" he says to himself.

"Hi, Sherlock!"

He pauses, looking over his shoulder. The boy from earlier is waving at him, grinning. "Billy," he starts. "Hello." He wants to continue walking, but Billy rushes towards, arms flying everywhere. "Oh, God," he breathes out.

"What did you get in there?" he asks, pointing at the bookshop down the street.

Sherlock lifts up his book for a split second. "It's for my mother."

Billy smiles up at him. "I always wanted to go in there, but my friends told me I wasn't allowed."

"Why aren't you allowed in there? It's just a bookshop."

"They told me it's a different kind of bookshop. I wouldn't belong in there, they said."

Sherlock raises an eyebrow and scans the little boy. "You wouldn't belong"—his eyes widen—"oh, right." He looks around the area and dips down, getting down to his level. "You don't live around here, do you, Billy?" He holds his book to his chest with an arm and uses the other to reach out and touch the woolen coat he's wearing. "You don't live around here at all." Giving him a small smile, he lowers his hand. "Do you know where you are?"

Billy stares at Sherlock with wide eyes. He picks at a spot on his coat. "What are you talking about?"

Scooting close, he shakes his head. "How did you get here? I thought there were enchantments, protections to prevent Muggles from entering Wizarding communities."

"I'm not a Muggle! I'm a"—he looks around before leaning in—"Squib."

Sherlock stands up and glares at the nearby houses. "A Squib!" he hisses. "Of course. Obvious."

Billy punches his legs. "Don't say it out loud!" He frowns and looks up. "Mama says it's very bad."

"I think it's fascinating." Sherlock smiles and looks down at the child. "Are you hungry, Billy? We have plenty of food at home." He presses his book to the child's chest and spins, starting down the street. "You won't be missed, will you?"

Billy hurries after him.

* * *

Sherlock and Billy are seated at the kitchen table, the younger eating a lunch provided by Bunsen. The house elf was eager to please the visitor, and after a talk with Sherlock, would be receiving a gift on Christmas if he neglected to mention the child to his parents and brother. Sherlock silently watches Billy, eyes narrowed in thought.

Billy stares back and licks his fingers. "What?"

"I might need you for something. Would that be a problem?"

"Nope," he simply says.

Sherlock leans back in his chair and runs his fingers over his top lip. "Excellent."

* * *

The adults arrive home hours later. Sherlock shoves Billy into the corner of his closet with bundles of yarn, knitting needles, and the book he purchased. He slips off to join the rest of his family, knowing all too well he would be chastised by Mycroft for doing nothing productive with his day. Sherlock keeps his comments to himself as he would nick his brother's wand before the night is up.

So, that night, with his parents and brother tucked away into their rooms, Sherlock creeps back into his bedroom, Mycroft's wand shoved in his pocket. He shuts the door, Sebastian quickly slipping in behind him. He stays still, his hand on the doorknob. He tilts his head and shuts his eyes. Taking a deep breath, he drops his hand. "Billy?"

"Yeah?"

Sherlock opens his eyes and walks over to the closet. He pulls the door open and sees the boy sitting down, the items he had given him sprawled out around him. He studies him. "How's that scarf coming along?" he asks carefully, glancing at Sebastian, who had positioned himself on the desk by the window. The Siamese cranes his neck to look outside.

Billy stands up, sending the work in progress to the floor. "Not very," he says angrily. "Can I come out now?"

Dipping down, Sherlock picks up the scarf and wraps it around his arm. He nods and gestures to the window. "Open it." He gathers up the knitting needles and the book. Billy walks past him and stands on his tip-toes to reach the window. Sherlock furrows his brow and tilts his head, running his fingers across the scarf. He hums.

"Should there be books here?"

"What?"

"There are a few books here. Just balanced on the sill." Billy stretches out his arms. "Can't reach them." Sherlock's eyes widen, and he walks over, tossing everything on his bed. He slips an arm around Billy's waist and picks him up, lifting him out of the way. He peeks out of the window, and, on the sill, a small stack of books were poised. He smiles and reaches out, pulling them inside.

"Brilliant." He wipes the covers off and studies the spines. The majority of the books are generalized Dark Arts ones, possibly only containing the term 'Horcrux' once or twice. After the third tome, he grins. He places the remaining books on his desk, Sebastian immediately beginning his own investigation. Sherlock runs his fingers over the title.

"_Secrets of the Darkest Art_?" Billy quietly asks. He stands beside the taller and frowns. "That doesn't sound good."

"Oh, Billy. It is very good." Sherlock opens up the book and flips to the table of contents. He taps his finger against each section, smiling again.

Billy takes a step back towards the closet. "I don't like it. It gives me a bad feeling."

He sets the book down on the bed and glances at the other. "Wait here. Play with Sebastian." Sherlock starts towards the door and stops. He looks over and points at the desk. "Give me that book there. The yellow one." Billy obeys without question, grabbing the yellow book from the corner of the desk and walking it to Sherlock. Their hands touch for a brief moment, causing Sherlock to glance at him. He shakes his head and turns away. "Thank you."

He exits the room and shuts it. He reaches into his pocket and takes out Mycroft's wand. He points at the door. "_Muffliato_." Spinning towards his sibling's and parents' door, he repeats the incantation. Sherlock stands a little straighter, slipping the wand into his pocket, and walks into the kitchen, going over to stand by the counter. He sets the textbook down and flips it open. He skips through the pages before landing on the one he wants. "Bloodroot Poison," he softly says. He eyes the list of ingredients, knowing that his mother would have all of them locked away in her cabinet. He claps his hands together and turns on his heel, going to the cabinet in question. He taps the wand against the handle and tugs it open, the various vials and containers looking at him. He smiles and bounces on the balls of his feet. Starting to pick out each ingredient, he hums again.

He places each object on the countertop as he reads the list again. After, he ducks down and drags out his mother's cauldron. He heaves it onto the stove, grabs his book, and moves it beside the item. He takes a deep breath and scans the area. "Aha," he breathes out, walking across the room and into the nearby bathroom. He opens up the medicine cupboard and digs out a face mask. "Almost forgot." He slips it on and stares at himself in the mirror. Sherlock narrows his eyes at his reflection. "Don't," he mutters. "No worries." Despite this, he feels his stomach knot up. He squeezes his eyes shut. "You've made it this far." He presses his fingers to his temples.

"Master Holmes?"

Sherlock's eyes snap open. He spins around and flicks his wand. "_Stupefy_!"

Bunsen grows limp and falls back with a thud. Sherlock stays still and breathes heavily. He stares at the stunned elf and slowly lowers the wand. He frowns and walks past the fallen, back into the kitchen. "All of this for a taste of immortality."

* * *

_Bloodroot Poison is a potion that causes the drinker to suffer severe pain and spasms, which cannot be healed in any way apart from consuming a bezoar. Without the aid of an antidote, the drinker will be dead in a matter of minutes._

Sherlock steps back into the bedroom, a cup of the dark liquid in one hand, a skull tucked underneath his other arm. He gingerly shuts the door and stands in the middle of the room, staring at Billy, who is seated on the bed with Sebastian in his lap. Billy looks at him, brows furrowed. "Where'd you get that skull?"

"The mantle in the living room."

"What's in your hand?"

"Juice."

"Are you going to kill me?"

"Where on earth would you get that idea?"

He walks over and sits beside him on the bed. He pushes the scarf away and looks over at the boy. Studying him, he holds out the cup. "I thought you might be thirsty."

Billy stares at him and roughly swallows. "I'm fine."

"Please." Sherlock pushes it towards him. "I made it with care."

Billy looks at the cup and bites his lip. He reaches out and takes the cup from the other's hands. He holds it under his nose and takes a deep breath, wrinkling his nose. Sherlock looks down and pulls _Secrets of the Darkest Art_ towards him. He flips to the section about Horcruxes and skims the page.

"What's a Horcrux?"

Sherlock slowly turns his head and stares at the younger. He blinks. "Drink."

The dirty boy looks into the cup one last time before wetting his lips. He starts to shake his head. "I don't want to." Sebastian leaps off the bed and runs towards the door.

"Oh, for God's sake," Sherlock mutters. He holds up his wand and points it at Billy, who stares at him with wide eyes.

"You are going to kill—"

"—_Obliviate_."

Billy's eyes glaze over for a second, before slowly fading back to their original color. He furrows his brow and blinks at Sherlock. "What's going on?"

"You're just about to take your medicine, Billy." He sets his wand down and reaches out, touching the bottom of the cup. He guides it to the other's lips, starting to tip it. Billy grips the sides and tilts his head back, drinking the potion.

He falls against the bed, and the cup slips from his hand, clanging against the floor. He screws up his face and lets out a wail. His toes curl as his legs bend towards his chest. Sherlock gives the skull a look before reaching out, grabbing the unfinished scarf and knitting needles. He pulls it to his lap and starts to work, the sounds of Sebastian's yowls and Billy's screams filling his ears.

He glances at him. "Now, now, don't die on me just yet. I want to get a section of this done."

He only receives a shudder.

* * *

Several days later, Sherlock Holmes and John Watson are seated in the Great Hall. John, a long, mismatched scarf around his neck, laughs and watches as Sherlock struggles with a Sudoku cube.

* * *

_John,_

_I'm about to leave for King's Cross, so this letter will be hand delivered to you. Your letter came here a few days ago. Well, it came to my attention a few days ago. I might have received it earlier, but I've been busy. Not too busy to not get you a Christmas gift, though. See, I remembered._

_My holiday has been dreadfully boring. I'd imagine yours went only slightly better._

_I won't write much in here. We can talk in person. We have a lot to catch up on._

_(If you ever use that many parentheses again, I'll have to hex you.)_

_Sherlock_


End file.
